<template>
  <view>
    <view class="search-box">
      <!-- 使用uni-ui 提供的搜索组件 -->
      <uni-search-bar @input="input" :radius="100" cancelButton="none"></uni-search-bar>
    </view>
    <!-- 搜索历史 -->
    <view class="history-box" v-if="!kw">
      <!-- 标题区域 -->
      <view class="history-title" >
        <text>搜索历史</text>
        <uni-icons type="trash" size="17" @click="cleanHistory"></uni-icons>
      </view>
      <!-- 列表区域 -->
      <view class="history-list">
        <uni-tag :text="item" v-for="(item,index) in historys" :key="index" @click="gotoGoodsList(item)"></uni-tag>
      </view>
    </view>
    <!-- 搜索建议列表 -->
    <view class="sugg-list" v-else>
      <view class="sugg-item" v-for="(item,index) in searchResults" :key="index" @click="gotoDetail(item.goods_id)">
        <view class="goods-name">
          {{item.goods_name}}
        </view>
        <uni-icons type="arrowright" size="16"></uni-icons>
      </view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        timer: null,
        //搜索关键字
        kw: '',
        // 搜索结果列表
        searchResults: [],
        // 搜索历史数据
        historyList:[]
      };
    },
    onLoad(){
      this.historyList = JSON.parse(uni.getStorageSync('kw')||'[]')
    },
    computed:{
      historys(){
        // 得到historyList翻转后的数组,且不改变historyList数组
        return [...this.historyList].reverse()
      }
    },
    methods: {
      // 点击历史搜索跳转到商品列表页面
      gotoGoodsList(kw){
        uni.navigateTo({
          url:'../goods_list/goods_list?query='+kw
        })
      },
      // 清空搜索历史记录
      cleanHistory(){
        this.historyList=[]
        uni.setStorageSync('kw','[]')
      },
      // 输入框内容发生变化时触发
      input(e) {
        clearTimeout(this.timer)
        this.timer = setTimeout(() => {
          this.kw = e
          this.getSearchList()
        }, 500)
      },
      // 获取搜索列表数据
      async getSearchList() {
        // 关键字为空
        if(!this.kw) return this.searchResults=[]
        const {data} = await uni.$http.get('/api/public/v1/goods/qsearch', {
          query: this.kw
        })
        if (data.meta.status !== 200) return uni.$showMsg()
        this.searchResults = data.message
        this.saveSearchHistory()
      },
      // 跳转到商品详情页面
      gotoDetail(goods_id){
        uni.navigateTo({
          url:'/subpkg/goods_detail/goods_detail?goods_id='+goods_id
        })
      },
      // 保存搜索历史记录
      saveSearchHistory(){
        // 将Array数组转化为Set对象
        const set = new Set(this.historyList)
        // 先进行删除 再添加,是为了该条历史搜索提前
        set.delete(this.kw)
        set.add(this.kw)
        this.historyList = Array.from(set)
        // this.historyList.push(this.kw)
        // 将搜索历史记录持久化存储到本地
        uni.setStorageSync('kw',JSON.stringify(this.historyList))
      }
    }
    
  }
</script>

<style lang="scss">
  .uni-searchbar {
    display: flex;
    flex-direction: row;
    position: relative;
    padding: 16rpx;
    background-color: #c00000;
  }

  .search-box {
    position: sticky;
    top: 0;
    z-index: 999;
  }
  .history-box{
    padding:0 5px;
    .history-title{
      display: flex;
      justify-content: space-between;
      align-items:center;
      height: 40px;
      font-size: 13px;
      border-bottom: 1px solid #efefef;
    }
    .history-list{
      display: flex;
      flex-wrap: wrap;
      .uni-tag{
        margin-top: 5px;
        margin-right:5px ;
      }
    }
  }
  .sugg-list {
    padding: 0 5px;

    .sugg-item {
      font-size: 12px;
      padding: 13px 0;
      border-bottom: 1px solid #efefef;
      display: flex;
      align-items: center;
      justify-content: space-between;

      .goods-name {
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
        margin-right: 3px;
      }
    }
  }
</style>
